Wind power is one of the fastest-growing sources of new electricity supply and the largest source of new renewable power generation added in the United States since 2000. More than 52,000 wind turbines are operating in 40 states and U.S. territories. While wind energy supplies clean, renewable power, wind facilities can affect sensitive wildlife species such as bats and eagles through direct collisions, and indirectly through loss of habitat when they are sited on undeveloped lands.
The USGS has made significant strides in addressing research needs identified by resource managers and industry to understand wildlife interactions with turbines, estimate causes and magnitude of fatalities, develop wildlife and mortality survey protocols, assess population effects, describe migrations and movement patterns, and develop potential mitigation measures.
Managers and industry operators are now using novel camera imaging techniques and statistical tools developed by the USGS to monitor bat behavior and estimate wildlife fatalities at wind facilities. In collaboration with wind operators, USGS is testing the effectiveness of ultrasonic acoustic devices to reduce bat fatalities at a lower cost. The USGS is also working with Iberdrola Renewables to pilot test the use of dim ultraviolet light to deter bats from interacting with turbines, and thereby, reduce fatalities.
Golden eagles can be killed by colliding with a number of human-made objects, including wind turbines. USGS research wildlife biologist Todd Katzner describes his studies of golden eagle flight. This research is being done to model flight behavior which might help managers understand how placement of wind turbines might pose significant risks to golden eagles.
At several wind power-generation facilities in the eastern, central, and western United States, we are conducting fatality searches for bat carcasses in order to relate fatality pattern to measures of bat activity, as well as to daily environmental conditions (e.g., weather, moon phase, day of year).
Since 2003, Northern Prairie Wildlife Research Center has conducted research on the impact of wind-energy development on breeding grassland birds in North Dakota and South Dakota, specifically addressing whether birds are displaced by wind infrastructure.
USGS and University of Minnesota collaborators used acoustical and ultrasonic recorders to monitor flight notes of birds and calls emitted by bats flying at low elevations. Recorders were deployed in conjunction with ongoing fatality searches at wind facilities and at sites with a variety of landscape features.
The first step in understanding the impact of wind energy development is to determine where the wind turbines are located. Prior to this study, there was no publicly available national-level data set of wind turbines.